This invention relates to an apparatus for cutting and notching sheet material, and deals more particularly with a cutting head having a rotary cutting tool for cutting limp sheet material along a cutting path and a second cutting tool for forming notches in the sheet material adjacent the cutting path.
It is known that limp sheet material spread in a single or low-ply arrangement over a hard, smooth support surface can be cut by a rotary cutting wheel as the wheel is pressed against and rolled across the surface of the sheet material. The cutting operation of the material is effected by the partial slicing and partial crushing action between the periphery of the wheel and the support surface. A rotary wheel and hard support surface combination is utilized in the apparatus described in U.S. Pat. No. 4,373,412, having the same assignee as the present invention.
In cutting pattern pieces from sheet material, it is often desired to produce marking or index notches at various points along the principal or desired line of cut, these marking notches being later used, for example, to align various pattern pieces relative to one another in preparation for a sewing operation or the like. Generally the marking notches are relatively short slits which are cut in the material perpendicular to the principal line of cut or edge of a pattern piece.
In the past marking notches have usually been cut by lifting, rotating and lowering the cutting tool to bring the tool into proper orientation for cutting before the tool is moved inwardly of the piece beyond the principal line of cut to produce the notch. The notch may be cut immediately upon reaching the notch point or by cutting along the principal line of cut past the notch point and later returning to cut the notch. Either procedure, however, involves a substantial amount of maneuvering of the cutting tool and a substantial consumption of time.
It has been suggested in U.S. Pat. No. 3,766,813 that the tool lifting and lowering steps may be eliminated. However, when the cutting tool is a cutting wheel, the segment of the wheel periphery buried in the sheet material cannot be turned without twisting the material surrounding the wheel. Additionally, the sharp peripheral cutting edge of the segment tends to produce significant gouges in a soft underlying support surface.
A general object of this invention, therefore, is to provide an improved apparatus for cutting and notching sheet material whereby the time required for cutting notches is substantially reduced.
A more specific object of the invention is to provide an apparatus for cutting notches substantially "on the fly" as a rotary cutting blade is moved along a principal line of cut and a second cutting tool in the apparatus moves into and out of cutting engagement with the sheet material along the line of cut to thereby form notches at desired locations.